Switch actuator unit



J 1967 P. c. R. FERNBERG 3,295,376

' swmcn ACTUATOR UNIT Filed April 20, 1964 1o V 19 a 19 1% Q 19 I 18 18 18 FIG WVENTOE I 5 Paa/ (ar/ floyermbery,

Afro Hey.

United States Patent free 3,296,876 SWIiTCH AQTUAT UR UNli'i Paui Carl Roger Fernherg, Farnham Common, Engiand, assignor to United-Carr incorporated, a corporation of Deiaware Filed Apr. 20, 11964, Ser. No. 366,874 Claims priority, appiication Great Britain, May 3, 196$, 17,606/63 3 Claims. ((Jl. 74-11%) The present invention relates to an improved two way switch, which is particularly but not exclusively suitable for use in television sets to give a push button switch between two channels.

According to the invention there is provided a two way switch comprising a link pivotted intermediate its length for limited rotation on a support, a U-shaped spring and a fixed member, in which the U-shaped spring is attached between the link and the fixed member to exert a permanent rotation force on the link in one or other rotational direction to either side of a dead centre position, an actuating member attached to each end of the link and operable to rotate the link against the action of the spring up to and through the dead centre position and means on the link adapted to operate a mechanism in response to rotation of the link.

Preferred embodiments of the invention will now be described with reference to the accompanying diagrammatic drawings, in which:

FIGURES 1 and 2 are respectively a plan and under plan of a two way switch,

FIGURE 3 is a plan similar to FIGURE 1 showing the switch at dead centre,

FIGURE 4 is a section on the line IVIV of FIG- URE 3,

FIGURE 5 is a plan view showing a part of a modification of the switch of FIGURE 1, and

FIGURE 6 is a section on the line VIVI of FIG- URE 5.

In FEGURES 1 to 3 a two way switch is indicated generally at it which in one of its applications may be installed in a television set to give a push button changeover from 465 line to 625 line reception.

The switch it? comprises a support panel 11. having a raised end flange 12 and a transverse shallow channel 13. Two parallel key hole shaped slots 14, 14a are formed in the support at right angles to the flange 12 and a link 1% is pivotted to the support by a rivet 16 which is similar to that described and claimed in our copending application No. 218,287.

Each end of the link 15 has an aperture 17 and 17a respectively, which overlies one of the slots 14-, 14a in the support panel.

The flange 12 of the support panel is formed with two slots (not referenced) and shafts 1%, Ida respectively, extend through the slots in the flange.

The free ends of the shafts 18, 18:: project from the flange and carry finger buttons 11), 19a respectively, which are attached to the shafts in any suitable manner. The opposite ends of the shafts 13, 18a are formed with apertures 2t), 2a and are pivotted to opposite ends of the link 15 by similar pivot pins 21 and 21a respectively.

The pivot pin 21 comprises a cylindrical shank 22, which is a clearance fit through the enlarged portion of the key hole slot 14- and which has a circumferential groove 23 adapted to accommodate and overlap the parallel side edges of the narrower portion of the key hole siot l4, and a head 24.

The head 24 overlies and abuts the shaft 18 and an axial bore 26 extends through the head 24 and into the shank 22. The upper surface of the head 24 has an angled groove 25 which is undercut at 28.

3,296,876 Patented Jan. 10, 1967 The shafts 18, 18a are assembled on the support panel 11 in the following manner.

Each pin, 21, 21a is passed, shank first, through the aperture in a shaft and then through an aperture in the link 15.

The link 15 is then brought up to the suport panel 11 and the shank of each pin is passed through the major portion of a key hole slot in the support panel. Finally the link and the pins are slid along the slots 14, 14a until the rivet holes in the link and support panel for the rivet to are aligned. The rivet 16 is then inserted and secured to pivot the link securely to the support panel.

When the shafts 18, 1812 have been secured to the support panel 11 in this way it will be seen that they are constrained in the slots 14, 14a for lengthwise movement alongtheir axes and that movement of one of the shafts in one direction produces opposite movement of the other shaft through the rotation of the link 15 about the rivet 16.

Rotation of the link 15 and thus lengthwise movement of the shafts is limited by a raised arm 22 which extends outwardly from the link and is then bent downwardly into the channel 13 in the support panel 11. When the link is rotated the arm butts against the shafts 18 and 18a thus limiting the angle of rotation of the link 15 and preventing the pivot pins from riding down into the enlarged portions of the key hole slots.

A spring 3% in the shape of a U having a web, two limbs and outwardly turned feet 31, 31a is attached between the arm 29 and the flange 12 with the outwardly turned feet 31 and 31a engaged in apertures formed respectively in the flange 12 and the free end of the arm 29.

The spring 33 is under maximum tension at dead centre when the arm 29 is parallel to the shafts 18 and 18a and on either side of this dead centre position it exerts a permanent force on the link tending to rotate it in one or other angular direction away from the dead centre position.

To complete the assembly of the switch unit 10 two sheathed cables 32 and 32:: are attached to the panel 11 by clips 33 and 33a which are of the type described and claimed in my Patent N 0. 917,898.

The inner cables 34 and 34a which are free to move within their sheaths are attached to the pins 21 and 21a by bending the end of the cable over and forcing it into the bore in the pin.

Referring to the inner cable 34, the end attached to the pin 21 is bent at right angles and secured in the axial bore 26. The pin 21 is then rotated so that the cable snaps into the undercut 28 which prevents the cable from being withdrawn from the bore.

It will be seen that when either of the shafts 18 or 18a are depressed the other shaft is automatically raised through the action of the rotating link 15.

Movement of the shafts 18 and 18a is transmitted directly to the inner cables 34, 34a respectively which may be used to actuate any mechanism to which they are connected.

Thus the switch it acts as a two button dual control switch which ensures, by means of the spring 3%, that the link 15 cannot remain at dead centre and that one of the two control cables 34, 34a is always in its operative position.

In order to disassemble the cables 34, 34a from the pins, the pins are twisted through approximately so that the cables are clear of the undercut slots 28. The cables are then withdrawn from the pins.

The undercut slots 28 are preferably provided with an overhang so that the inner cables snap into position and the pins are then held against accidental rotation.

A modification of the invention is indicated generally at 4t? in FIGURE 5.

The switch 40 is similar to the switch except that the inner cables 34, 34a and shafts 18, 18a are attached together and pivoted on the support panel 11 in a different manner.

In the switch 40 the link is provided with a hearing member 41, which rotates in an aperture 42 in the support panel 11, and each shaft 18, 18a is held to the link 15 with the aid of a-pin 43 and 4311 respectively.

The pins 43, 43a are similar and only the pin 43 will be described in detail.

The pin 43 comprises a stepped shank 46 having a tail 44 of increased diameter and a head 47 formed with two diametrically opposed lugs 48, 48a the free end of each of which has an overhang 49, 49a.

The support panel 11 is formed with parallel sided slots 50, 50a and, in order to assemble the switch 4% the lugs 48, 48a of each pin are aligned with and then passed through each slot until the enlarged tail 44 butts against the support.

The pins are then rotated through 90, so that the lugs extend across the slot, and the link 15 which has apertures 51, 51a respectively of such dimensions as to accommodate the lugs 48, 48a of the pins is placed over the pins and pressed down onto the panel 11, with the bearing member 41 located in the bearing aperture 42 in the panel.

The pins 43, 43a are again rotated through 90 and the shafts 18, 18a which are formed with apertures 52, 52a similar to the apertures 51, 51a are pressed over the pins which are again rotated through 90.

In the final position, as shown in FIGURE 6 the overhang on each lug resiliently grips the side of the shaft to resist further rotation of the pin. The shafts 18, 18a are thus pivotted securely to the link 15 and support panel 11 and are free to move within the limits imposed by the slots 50, 50a in the support panel.

The upper face of the head 47 of each pin has a diametrical undercut groove 53 and an axial stopped bore 54.

The inner cables 34, 34a are attached to the pins 43, 43a by bending the end of each cable through 90 and pressing the end into the bore 54 in the stud until the cable itself snaps into the undercut groove 53.

The switch 40 functions in the same manner as the switch 10 but has the advantage that the inner cables may be removed by levering them out of the pins, whereas in the switch 10 pins 21, 21a have to be rotated before the cables can be removed.

The spring 30 on the switch 10 may be any shape which will give the resilience necessary to ensure that the switch cannot remain at dead centre, for instance, it may be approximately S-shape.

The pins 21, 21a may also be provided with flats on the groove 23 so that, when assembled they cannot turn in the narrower portion of the key hole slots 14, 140.

What I claim is:

1. A two way switch actuator comprising a link pivoted intermediate its length for limited rotation on a support, a spring and a fixed member, in which the spring is attached between the link and the fixed member to exert a permanent rotational force on the link in one or other rotational direction to either side of a dead centre position, an actuating member attached to each end of the link, said actuating members comprising two shafts arranged in parallel relationship and constnained for lengthwise movements along their own axes and operable to rotate the link against said support having two parallel slots running lengthwise of the direction of movement of the shaft and a pin pivotally connecting each shaft to the link and extending through a slot in said support for sliding movement therealong, each pin having an axial bore and a cable engaged in said axial bore in each pin for movement in response to rotational movement of the link.

2. A two way switch actuator as claimed in claim 1, in which each slot in the support is of key hole shape having an enlarged portion and a narrower portion and each pivot pin has a 'head and a cylindrical shank formed with a circumferential groove, the dimensions of the shank and groove being such that the shank will pass freely through the enlarged portion of the key hole slot and the groove will overlap and ride along the edges of the narrower portion and rotational movement of the link in both directions is limited by abutment of the arm against the shafts.

3. A two way switch actuator comprising a link pivoted intermediate its length for limited rotation on a support, a spring and a fixed member, in which the spring is attached between the link and the fixed member to exert a permanent rotational force on said link in one or other rotational direction to either side of a dead centre position, an actuating member attached to each end of said link and operable to rotate the link against the action of the spring up to and through the dead centre position, said actuating members comprising two shafts arranged in parallel and constrained for lengthwise movement along their own axes, said support provided with two parallel slots running lengthwise of the direction of movement of said shafts and each being of key-hole shape, having an enlarged portion and a narrower portion and a pin pivottally connecting each of said shafts to said link and extending through one of said slots in said support for sliding movement therealong, each of said pins having a head and a cylindrical shank formed with a circumferential groove, the dimensions of said shank and groove being such that said shank will pass freely through the enlarged portion of said key-hole slot and said groove will overlap and ride along the edges of the narrower portion thereof.

References Cited by the Examiner UNITED STATES PATENTS 472,610 4/1892 Stanley 20072 1,132,470 3/1915 Gordon 74-100 X 1.143.606 6/1915 Both 74100 2,523,786 9/1950 Spremg 74100 X 2,594,216 4/1952 Roeser 74100 X FRED C. MATTERN, 111., Primary Examiner.

F. E. BAKER, Assistant Examiner, 

1. A TWO WAY SWITCH ACTUATOR COMPRISING A LINK PIVOTED INTERMEDIATE ITS LENGTH FOR LIMITED ROTATION ON A SUPPORT, A SPRING AND A FIXED MEMBER, IN WHICH THE SPRING IS ATTACHED BETWEEN THE LINK AND THE FIXED MEMBER TO EXERT A PERMANENT ROTATIONAL FORCE ON THE LINK IN ONE OR OTHER ROTATIONAL DIRECTION TO EITHER SIDE OF A DEAD CENTRE POSITION, AN ACTUATING MEMBER ATTACHED TO EACH END TO THE LINK, SAID ACTUATING MEMBERS COMPRISING TWO SHAFTS ARRANGED IN PARALLEL RELATIONSHIP AND CONSTRAINED FOR LENGTHWISE MOVEMENTS ALONG THEIR OWN AXES AND OPERABLE TO ROTATE THE LINK AGAINST SAID SUPPORT HAVING TWO PARALLEL SLOTS RUNNING LENGTHWISE OF THE DIRECTION OF MOVEMENT OF THE SHAFT AND A PIN PIVOTALLY CONNECTING EACH SHAFT TO THE LINK AND EXTENDING THROUGH A SLOT IN SAID SUPPORT FOR SLIDING MOVEMENT THEREALONG, EACH PIN HAVING AN AXIAL BORE AND A CABLE ENGAGED IN SAID AXIAL BORE IN EACH PIN FOR MOVEMENT IN RESPONSE TO ROTATIONAL MOVEMENT OF THE LINK. 